Automatic steam blower



Nov. 7, 1933. J. T. CRUTE 1,933,658

AUTOMATIC STEAM BLOWER Filed March 23, l93l TO THE 6 TA 38 7 I s $72? .96 37 35 32 G 35 7 1 INVENTOR.

a4 jaw L Q7 6 & Y] TO THE ENG/N5 ATTORNEYS Patented Nov. 7, 1933 UNITED STATES AUTOMATIC STEAM BLOWER I Joseph Thomas Crute, Virgilina, .Vafassignor of one-half to Marvin A. Goode, Virgilina, Va.

Application March 23, 1931. Serial No. 524,743

- 4 Claims. o1. 110 15o)' This invention relates to an automatic steam blower. It is primarily designed for use in conjunction with such mechanisms as sawmill' engines where the load varies greatly at shortly separated intervals and wherein the exhaust steam from the engine is used as a blower to increase-the draft of the fire in the boiler that is supplying steam to the'engine. It is the usual practice to turn the exhaust steam of sawmill engines into the stacks of the furnaces to increase the draft. When the saw is passing through a log, the governor opens the steam supply valve and a large quantity of steam is supplied to the engine and this steam, in turn, is exhausted into the stack and a good draft is secured.

However, after the saw passes from the log, the

load upon the engine is relieved and the engine runs light. The result is that the governor partially closes the steam supplyvalve and very little steam is supplied to the engine and, consequently, to the exhaust line, so that the blower effect in the stack practically ceasesQ The purpose of the present invention is to provide means for automatically continuing the blower effect so that the draft will be continued during the time that the engine is running light and I accomplish this by providing means associated with the governor through which steam is supplied direct.- ly to the stack when thegovernor is in its closed position. It will be seen, as this description proceeds, that the supply of blower steam to the stack automatically varies with the load upon the engine, under the influence of a speed re,- sponsive device such as a centrifugal governor, 3 in such manner that just the amount-of live blower steam will be delivered to the stack to fit the conditions under which the engine is operating. a

In the accompanying drawing, Figure 1 is a view partly in side elevation and partly in section of the governor having the improvements of the present invention applied thereto.

Fig. 2 is a detailed view of a rock yoke herein- 415 after described. Fig. 3 is a detailed View of the connection between a valve and its stem, hereinafter described. Q Like numerals designate corresponding parts in all the figures of the drawing,

In the drawing, 5;designates the valve body of the well known Pickering centrifugal governor. These governors comprise a main valve .6 which controls the passage of steam from a main steam supply line 7 tothe steam outlet 8 from where the steam passes to the steam chest of the en'- gine. Movement of the valve 6 to vary the supply of steam which may pass from 7 to 8 i's effooted under the influence of balls 9 which are thrown outwardly by centrifugal force and are carried by resilient members 10 that are secured to a, rotated collar, at 12. ,Said'coliar is driven from any suitable portion of the engine mechanism, not shown, by means of the bevel gear 13. If the engine. speeds up, abnormally, because of reduced load the balls 9 fly outwardly under the influence-of. the rotation imparted to them from collar 11 and in so doing draw a head 14' downwardly. This head is carried by the valvestern 15 which partakes of the downward movement of said head and in so doing -moves the valve 6 toward closed position.

The movement of the valve 6 downwardly is resisted by a spring actuated yoke 16 which engages beneath a collar 17 ofthe stem 15. This yoke is mounted upon a shaft 18 and said shaft is surrounded by aspring 19 and said spring is engaged with the yoke,as indicated at 28 in Fig. 2, in such a manner that the spring tends to move the yoke upwardly.

The structure as far as described is the structure of the oldand well known Pickering governor which is notfmy invention;

One embodiment ofmy invention is achieved by extending the hub 16a of the yoke to form an outwardly projecting arm 20 which serves as a point of attachment for-the bifurcated member 21. A valve stem 22 is adjustably connected'with the member 21 by being threaded theret'o'and is provided with a lock nut 23. The st'm22 has an enlarged ball-like end 24, see Fig. 3,'which' is ,seated'in a recess formed in'the upper'endof a plug valve 25. A sleeve 26 that is provided with an angular head 27 prevents outward movement .of the ball 24 and causes the valve 25 to' move with the stem. vThe opening 28 of the sleeve 26 through which the stem 22 passes; is'en'ough larger in diameter than said stem to, permit the stem to move to positions of slight angularit'y with respect "to valve 25 while permitting the latter to move in a straight line; The valve 25 passes through a stuffing box 29 and controls the passage of steam through a port 30 formed through a sleeve 31. This sleeve in turn extends across the, bore 33 of a nipple3 l that isthreaded at 35 into the valve body5,

A blower line 36 leads tothe stack and may be provided with any suitableform of controleling valve 37 by which the volume of steamdelivered through pipe 36, direct tdthe stack (not shown), may bev controlled; It is thought that 110 the operation of this device will be apparent. However, it may be stated that when the engine is running under load, and consequently under such reduced speed that the balls 9 are moved inwardly and the head 14, stem 15 and valve '6 are correspondingly elevated, a considerable volume of steam passes through '7 and 8 to the engine, and this considerable volume of steam in the form of exhaust steam is delivered into the stack for the purpose of maintaining a good draft therein.

When the load upon the engine is suddenly relieved, as for example, when the circular saw driven by the engine passes out of a log being cut,

the engine tends to speed up, the balls 9 fly apart, valve 6 is lowered and very little steam passes to the engine. This lowering movement of stem 15 thrusts the yoke 16 downwardly and elevates the arm 20 and valve 25, thereby perapply my improved mechanism to an existing structure, it is only necessary to tap a hole, as for example, that indicated at 38, in the governor body 5 for the reception of the nipple 34 and to substitute a yoke with the arm 20 for the conventional yoke of the governor. This is a change that may be made in a very short time and at a very small cost; I have found by experience that the structure shown in my accompanying drawing provides a governor having an important capacity of great utilityin, that it automatically acts to make the engine run faster when under load than when idling. Ordinarily, a governor is intended to keep the engine running at a uniform rate of speed irrespective of the load. Through the blower attachment herein shownand described'I not only automatically supply direct steam to the stack blower when the engine is running light, but I utilize the flow of this stack steam to slow, the engine down to a point beyond that at which it runs when under load, as, for example, when sawing through a log. This is of importance because an engine will run without very much vibration when under load but it will vibrate to an injurious extent at the same speed but under no load. The reason that these important results are achieved are as follows: The cutting off movement of the governor by which the amount of steam supplied to the engine is decreased is effected under downward movement of stem 15. Consequently, any influence which tends to bring about such downward movement also reduces the amount of steam supplied to the engine. When the load is relieved upon the engine and the balls 9 act to move thestem 15 downwardly such movement raises the piston 25, as previously described, and steam flows beneath said piston to the blower line 36. The pressure of the steam in the blower line, which is not very great, is still enough, acting uponrthe lower end of the piston, to tend to thrust piston 25 upwardly and to that extent to overcome the action of "spring 19 and bring about an additional lowering of the valve 6 of. the governor. It might seem, atfirst glance, that the same result could be secured by of an arm carried by said yoke, a blower line leadthe proper setting of the tension spring of the governor, but this is not the case, because in order to secure the advantages that I secure the tension of the governor controlling spring should be such as to open up' the steam supply to the engine to such a point as to get a desired relatively fast speed when sawing through a log, for example, but even this rate of speed is undesirably fast for the engine when running light and so I secure the additional advantage of reducing the engine speed when running light below what it is when sawing through a log.

While I have described my invention with particular'reference to sawmill engines, it is apparent that it is of utility in any relation where the load upon the engine varies frequently and to a considerable degree and where the exhaust from the engine is relied upon to maintain the draft in the stack. It would, of course, be possible to turn steam direct from the boiler into the stack to maintain the blower effect. However, this would be extremely wasteful, Under my invention live steam is utilized in the stack, only when exhaust steam is not available and exhaust steam is automatically brought into use when ever it is available, and to the exact degree required by the existing conditions as to the avail--' abilityof such exhaust steam. That is to say if the engine isdoing little work and delivering but little exhaust steam to the stack, a large amount of live steam" is supplied to the blower, while if the engine is doing a considerable amount of work and delivering considerable exhaust steam to the blower, a smaller amount of live steam is delivered through this attachment to the blower. If the engine is only partly loaded then both live and exhaust steam are supplied to the stack and in just the proper proportions.

It will be apparent that many ways will readily suggest themselves to those skilled in the art for accomplishing the desired result, and consequently it is to-be understood that the invention includes within its purview whatever changes fairly come within either the terms orthe spirit, of the appended claims.

Having described my invention, what I claim is:

' 1. The combination with a centrifugal speed controlled governor and its axially moving main valve, valve stem and yoke associated therewith,

ing from the governor casing, and an auxiliary valve controlling said blower line and connected to said arm movement of the main valve of the governor to closing position serving, through said yoke and arm, to move the auxiliary valve to open position.

2. The combination with a speed controlled governor and its axially moving main valve stem and main valve; of a rocking yoke engaged with said stem, an outwardly extending arm carried by said yoke, a valve stem pivoted te the outer end of said arm, a valve connec'ted to said valve stem, a stuffing box through which said valve passes, anda blower linecontrolled by said valve, said blower line being in communication with the space within the governor.

3. A structure as recited in claim 2, in combination with means for connecting the valve stem to the last named valve in such-amanner as to permit straight line'movement of said valve while permitting angular movement ofthe valve stem.

4. In a device of the character described, the combination with a speed controlled centrifugal governor having an axially moving ,mainvalve stem and valve, a yoke engaged therewith, ashaft 15G into which said last named valve projects, a nipple having a port formed therethrough which is traversed by said sleeve and is in communication with the interior of the. governor, and a blower line in communication with said nipple as and for the purposes set forth.

' J O SEIE'H THOMAS CRUTE. 

